Journal of Dental Medicine

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Statement of Problem: A few decades have past from using radiographic technology as an accurate paraclinical method and always protective measurements is applicated against ionizing radiation. As dental radiography is a routine procedure in dentistry the importance of protective strategies is clear.
Propose: The aim of this descriptive study is to evaluate the protection principles in centers which have intraoral radiographic devices in Yazd.
Material and Methods: We have considered all three aspects of practitioner, environment and patient protection using questionnaire and visiting those centers.
Results: 33/7% of dental offices ,10 clinics ,3 institution and faculty of dentistry had intraoral radiographic equipments. Stablishment of protection principles for radiographer was favorable. 7.7% of centers had x-ray room with leaded walls, 23.1% had curtain , in 69/2% of centers radiographers stood in correct position and distance while taking radiograph. Regarding to protection of environment, beams leakage control in 23.1% dental offices, 70% of clinics, all institution and faculty of dentistry have done.
Conclusion: Non of the centers used rectangular localizator, thyroid shield, film holder and just some centers used leaded apron in specific circumstances. We have concluded that patient protection constitute less consideration. Generally lack of protective consideration is related to deficient knowledge of operators. Lack of information about protection equipments causes decrease of demanding of these tools and ultimately lack of these equipments in the market.

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Background and Aim: Proper shaping and cleaning of the root canal system is one of the most important aspects of endodontic treatment. To estimate the canal length before instrumentation in endodontic treatment, traditionally, conventional radiographic techniques and recently Direct Digital Radiography (DDR) are applied. The application of computer technology to radiography has allowed less exposure time, image acquisition, manipulation, storage, retrieval, and transmission to remote sites in a digital format, elimination of wet processing and considerable reduction in the time lapse between image acquisition and display. The purpose of this study was to compare the accuracy of DDR versus conventional radiography in estimating endodontic file lengths of curved canals in first mandibular molars.

Materials and Methods: In this test evaluation study, fourty extracted human first mandibular molars with root curvature were selected.Samples were divided into two groups: With root curvature less than 25 and more than 25. Samples were mounted in plaster blocks and canal lengths were estimated by using DDR and conventional radiographs. Regression analysis and correlation coefficient were used to calculate statistical differences between the groups with P<0.05 as the limit of significance.

Results: Conventional radiography was more precise in canals with less than 25 degrees curvature (P=0.160). While, DDR was more precise for canals with curvature more than 25 degrees (P=0.605). However, these differences were not statistically significant.

Conclusion: The image quality of DDR system has improved to the point that it can now be used for estimating canal lengths, even for curved canals, with accuracy comparable to that of conventional radiography.

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Background and Aim: The goal of dental treatment is to improve oral hygiene, to maintain teeth and minimize the risk of diseases. Although data obtained from radiographs has distinct advantages to patients, the radiation side effects should be considered as well. FDA has developed a guideline for prescribing radiographs in the middle of the eighties. The aim of this study was to evaluate the reasons of ordering panoramic radiographs and their accordance with FDA guidelines in Tehran dental school.

Materials and methods: This descriptive study was carried out on 250 patients referred from different departments of Tehran dental school to radiology department for panoramic radiography. Chief complaints and clinical findings of patients were recorded in a check list and compared with the FDA guidelines prescribed.

Results: Our findings showed that prescription of panoramic radiographs were in accordance with FDA guidelines in 97.2% of cases.

Conclusion: Based of the results of this study, the trend of panoramic radiography ordering in the dental school of Tehran university is adequate. This may be attributed to the academic field of this study.

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Background and Aims: Overlapping of the proximal surfaces of posterior teeth in the panoramic radiography is a major concern. Therefore, an option has been developed in the panoramic unit of Planmeca Promax, namely improved interproximal mode. This mode causes lower horizental angle with the teeth contact region during the unit rotation decreasing overlapping of the panoramic images of the posterior teeth especially premolar teeth. The present study was done to compare the overlapping of posterior teeth using two techniques of improved interproximal panoramic program and standard panoramic.

Materials and Methods: In this diagnostic study, 32 patients requiring panoramic radiographies at their posterior teeth during their routine diagnosis and treatment process with the mean age of 27.3 years were participated. No patients showed crowding of posterior teeth or missed and restored posterior teeth. The participants' panoramic radiographies were randomly taken by two techniques of improved interproximal panoramic and standard panoramic using Planmeca Promax device. The overlapping of the panoramic images was blindly assessed by an oral radiologist. The overlapping in both techniques was reported by frequency and percentage. The comparisons were done by Chi-square test between two techniques and the odds ratio of overlapping was estimated using regression analysis.

Results: In standard panoramic techniques, 38.5% (148 contacts of 384 contacts) of the proximal surfaces overlapped while the overlapping of the proximal surfaces was observed in 18.8% (72 contacts of 384 overall contacts) in improved interproximal technique. Significant differences were noted between two techniques regarding overlapping (P<0.001). Also 66.4% and 39.1% of 4-5 teeth contacts overlapped in standard and improved techniques. The values were reported to be 39.1% and 12.5% in contacts of 5-6 teeth and 10.2% and 4.7% in the contacts of 6-7 teeth in both techniques, respectively. The overlapping odds ratio in improved technique as compared to standard techniques was 2.72 more. While the odds ratio of overlapping in the contact regions of 4-5 and 5-6 teeth was 16.4 and 4.61 as compared to the contact region of 6-7 teeth (all: P<0.001). The lower or upper jaw with the patients' mouth side did not significantly influence the overlapping of the proximal surfaces in both panoramic techniques.

Conclusion: Under the limitations of this study, improved interproximal panoramic significantly reduced the overlapping of proximal surfaces in the panoramic radiographies of posterior teeth as compared to the standard panoramic technique. Therefore, it can be used to detect proximal caries in the posterior teeth as a diagnostic tool. Using this option may affect other part of panoramic image which should be investigated in other research.

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Background and Aims: Conventional radiological equipments in our country are going to be converted to digital system using computed radiology (CR) technology. If we know the accuracy of digital panoramic radiography for detection of small defects in tooth, it will be useful in cases with difficulty for taking the intraoral radiographs. The aim of this study was to evaluate sensitivity and specificity of digital panoramic radiography for detection of proximal caries compared with the bitewing radiography.
Materials and Methods: One-hundred patients who had been ordered for taking both bitewing and panoramic radiography were included in this study. Panoramic and then bitewing radiographs were observed by a maxillofacial radiologist and interproximal caries were recorded. Sensitivity and specificity of digital panoramic radiography (CI=95%) was calculated compared with the bitewing radiography as a gold standard.
Results: This study showed that the values for sensitivity and specificity were 62.7% (CI 95%=57.7%-67.5%) and 91.0% (CI 95%=89.2%-92.5%), respectively.
Conclusion: Sensitivity of digital panoramic is less than bitewing radiography even with processing before printing. Therefore, bitewing radiography is superior for detection of inter proximal caries.